This invention relates to novel luminescent compositions and more particularly to such compositions containing lanthanide elements and hafnium. Such luminescent compositions, known generally as phosphors, emit visible light or other radiation when excited or irradiated by a different form of radiation, such as ultraviolet (U.V.), cathode ray (CR) or X-radiation. CR excitable phosphors are used, for example, in cathode ray tubes while U.V. excitable phosphors are used in fluorescent lamps and mercury lamps and x-ray excitable phosphors are employed in x-ray tubes.
It would be an advance in the art to provide new and useful phosphors for these applications.